Direction signal switch



y 1957 w. E. BROWN ET AL 2,800,541

DIRECTION SIGNAL. SWITCH 2 Sheefs-Sheet 1 Filed July 19, 1954 y 1957 w. E. BROWN ET AL 2,800,541

DIRECTION SIGNAL SWITCH Filed July 19, 1954 2 Shets-Sheet 2 United States Patent DIRECTION SIGNAL SWITCH William E. Brown and Ward Cole, Anderson, Ind., as-

signors to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application July 19, 1954, Serial No. 444,068

13 Claims. (Cl. ZOO-61.34)

This invention relates to direction signal switches and more particularly to manually set and automatically reset mechanisms for operating such switches.

Direction signal switch mechanisms which are manually settable to a switch operating position and automatically reset to neutral responsive to turning movement of the steering wheel are well known in the prior art. However, in the past, such mechanisms have in general been relatively complicated, difficultto assemble and required critical alignment. More recently, it has been found desirable to incorporate an overriding feature which prevents damage to the mechanism as a result of inadvertent or intentional holding of the operating lever against the cancelling action of the mechanism. Prior to the present invention, this later development has contributed still further to the complexity of structure of switch control mechanisms.

An object of the present invention is to provide a control mechanism for a direction signal switch which is manually adjustable from a neutral position to dilferent signal operat ing positions and is automatically returnable to the neutral position responsive to rotation of a vehicle steering wheel in a direction opposite that of the indicated turn.

Another object is to provide a mechanism of the stated character wherein a single member is effective to provide bypassing, automatic resetting and overriding in each signal operating position.

A further object is to provide a mechanism of the stated character wherein a single resilient member is mounted in a manner providing different degrees of flexibility when engaged in opposite directions, whereby the member is easily by-passed when engaged in one direction and offers high resistance when engaged in the other direction.

A further object is to providea signal control mechanism which is simple in construction, low in cost, and etlicient in operation.

These and other objects and advantages of the invention will become more apparent from the following description and drawings wherein:

Fig. 1 is a plan view of the control mechanism showing the location and arrangement of the parts thereof when the mechanism is in the neutral position.

Fig. 2 is an enlarged elevational view, partly in section and with parts broken away, looking in the direction of arrows 22 of Fig. 1.

Fig. 3 is a fragmentary plan View, partly in section, of a modified form of detent mechanism for the device.

Fig. 4 is an enlarged fragmentary side elevational view, with parts broken away, looking in the direction of arrows 44 of Fig. 3.

' Fig. 5 is a plan view similar to Fig. 1 showing the location and arrangement of the parts when the mechanism is in an operated position, and

Fig. 6 is a plan view of a modification of the invention.

Referring now to the drawings and particulanly Figs. 1 and 2, there is illustrated a cylindrical housing 2 which is disposed adjacent the upper end of a vehicle steering column 3 in concentric relation therewith. Housing 2 2,800,541 Patented July 23, 1957 may be secured to column 3 in any suitable manner and is provided with an axially intermediate web portion 4 which constitutes its base.

Disposed generally concentrically within the housing 2 is a relatively flat sheet metal switch operating ring 6. Ring 6 is rigidly secured at one end thereof to the upper face of a stud 8 by means of machine screw 10. Stud 8 is rotatably disposed in a downwardly extending bore 12 formed at one side of the housing 2. An operating handle 14 extends through a circumferential slot 16 in housing 2 and engages stud 8 to permit manual adjustment of ring 6 to its various positions.

Substantially diametrically opposite stud 8, an electrical switch 18 is mounted in a recess formed in web 4. Switch 18 is of the type commonly used in directional signal systems and is so constructed as to control the energization and deenergization of such systems. Switch 18 generally comprises a movable contact or bridging member 20 which is slidably mounted in a casing 22 and carries bridging contacts 24 adapted to engage fixed contact elements 26. Contacts 26 are, in turn, mounted in a terminal plate 28 which is secured at the base of casing 22 in any suitable manner. Fixed contacts 26 are connected to lead wires 30 which are arranged to provide circuit connections correlated with the adjusted positions of ring 6. On its top wall, casing 22 is formed with a transversely extending arcuate slot 32 through which extends an operating pin 34 formed integrally with bridging member 20. Pin 34 extends upwardly and operatively engages a laterally elongated notch 36 formed in ring 6 and is thereby movable to its various positions of adjustment responsive to swinging movement of ring 6.

Above and slightly to one side of slot 36, there is provided a cup-shaped outwardly facing member 38. Member 38 is formed with downwardly projecting supporting legs 39, which are rigidly secured to ring 6, as by welding. A cylindrical detent member 40 is slidably received within member 38 and is yieldably urged outwardly by coil spring 42. At its outer end, detent member 40 is formed with a conical tip 44, which yieldably engages the notched wall section 46 of housing side wall 48 to yieldably retain ring 6 in its various adjusted positions. Upon movement of ring 6 in either direction from the neutral position shown in Fig. l, detent member 40 recedes into cup-like member 38 against the pressure of spring 42, as tip 44 follows the inclined wall 50 or 52 of notched portion 46. Upon passing either crest 54 or 56 of notched portion 46, tip 44 is urged outwardly by spring 42 to engage the inclined shoulder 58 or 60, as the case may be, to yieldably retain the mechanism in either of its operating positions.

In Figs. 3 and 4, there is shown a modification of the detent construction shown in Fig. 1, wherein an outwardly facing cup-like member 62 is provided with integral downwardly depending walls 64 and 66 having longitudinal slots 68 and 70 formed therein which embrace the parallel edges 72 and 74 of an outwardly facing notch formed in ring 6. A slot 76 formed between legs 64 and 66 operatively engages upstanding operating pins 34 of switch 18. As seen particularly in Fig. 3, cylindrical detent member 78 is similar in form and is associated with member 62 in the same manner as previously described with reference to detent 40.

In order to provide automatic cancelling of a manually set signal operating position, in accordance with the present invention, ring 6 has secured thereto a resilient cancelling member 80. Member 80 is a generally U-shaped wire spring having integral pawls in the form of circular looped extremities 82 and 84 which are composed of one or more turns. Each loop 82 and 84 terminates in rela tively short legs 85 and 86 which extend laterally outwardly at substantially right angles to the straight portions 85 and 91) of member 80. Legs 85 and 86 terminate in short bent down tips 92 and 94. Tips 92 and 94, respectively, extend downwardly through apertures 96 and 98, formed at opposite sides of ring 6. Immediately adjacent the looped portions 82 and 84, ring 6 is formed with integral upstanding tabs 100 and 102 having outwardly extending bent over ends 184 and 106. Tabs 100 and 102 occupy positions adjacent the straight portions 88 and 90 of spring wire 88 and are effective as stop means to establish the normal position of loops 82 and 84 as well as to retain member 80 in assembled position on ring 6. As will be apparent from Fig. 1, the inner portions of loops 82 and 84 extend inwardly beyond the opening defined by the inner periphery of ring 6. Secured to the base of steering wheel 108 is a circular plate 110 to which is attached a downwardly depending cancelling pin 112 which function as a rotatable cam. When ring 6 is in the neutral position, the inner extremities of loops82 and 84 occupy positions which do not interfere with the circular path defined by cancelling pin 112 when steering wheel 108 is rotated. However, when ring 6 is manually shifted to the left turn switch operating position, the inner extremity of loop 82 moves inwardly with rings 6 to a position intersecting the circular path of pin 112. It will, of course, be understood that loop 84 will move with ring 6 to a corresponding but reverse position when ring 6 is moved to the right turn switch operating position. By virtue of the construction and arrangement of the cancelling member 80, either loop portion 82 or 84 will rotate yieldably outwardly about the axis of tip 92 or 94 when engaged by pin 112 from a direction similar to that of the indicated turn. By way of example, when the mechanism is in the left turn operating position shown in Fig. 5, it will be seen that resistance to clockwise rotation of loop 82 about tip 92 will be very slight, since the efliective anchor point for spring 80 will be the pivotal connection at 94. Thus, the flexing necessary to permit clockwise rotation of loop 82 will be distributed throughout virtually the entire length of the straight portions 88 and 30 and intermediate curved portion 89 of member 80. Upon reversal of the direction of rotation of cancelling pin 112, loop 82 will be engaged from the opposite direction and will tend to swing counterclockwise about tip 92. However, since counter-clockwise rotation of loop 82 induces inward swinging movement of the straight portion 88 of spring 80, only limited counter-clockwise rotation of loop 82 may take place before straight portion 88 engages tab 100. Thereafter, further counter-clockwise rotation of loop 82 is strongly resisted, since virtually all flexing of straight portion 88 must take place between tab 100 and loop 82. Consequently, when the rotative pressure of pin 112 on loop 82 exceeds the holding pressure of detent 48, ring 6 is cammed to the neutral position to automatically cancel the manually set signal. It will be understood that loop 84 responds to pin 112 in an identical manner except in the reverse sense when ring 6 is set in the opposite switch operating position. It will, thus, be seen that in the present invention, ring 6 and spring member 80 interact in a manner providing opposite extremes of flexibility of the spring member 80, whereby the loop 82 or 84 is easily displaced when approached from one direction and strongly resists displacement when approached from the opposite direction. Thus, only a single spring element of a simple configuration is required to provide the multiple function necessary to assure automatic operation of the mechanism.

In addition to the simplicity of structure and other advantages already enumerated, the form and arrangement of the present invention are such that damage to the mechanism by intentional or advertent operating procedure is completely eliminated. For example, if the operating handle 14 is forcibly maintained in the left turn signal operating position while the steering wheel is rotated in a direction opposite that of the indicated turn, the cancelling pin 112 initially induces counter-clockwise rotation of loop 82 until further rotation is restrained by tab 88. When the pressure of pin 112 becomes sufficiently strong, loop 82 is yieldably distorted locally to provide sufficient clearance for the pin 112 to pass without damage to the mechanism. It will be understood, of course, that the pressure required to distort either loop 82 or 84 is considerably greater than the resilient holding effect of detent 40 and, therefore, overriding of the signal cancelling operation takes place only when the mechanism is forcibly restrained or jammed by a foreign particle.

In Fig. 6, there is illustrated a modification of the invention wherein the U-shaped spring is provided with end portions 114 and 116 of triangular configuration. The terminal legs 118 and 120 of portions 114 and 116 are formed with eyes 122 and 124 which engage upstanding pins 126 and 128 secured on ring 6. Intermediate legs 130 and 132 of end portions 114 and 116 are inclined inwardly at shallow angles relatives to the path of pin 112 while the intermediate legs 134 and 136 extend inwardly at substantially right angles to the path of pin 112. It will, thus, be seen that legs 130 and 132 provide a low interference angle for pin 112 while legs 134 and 136 provide a high interference angle. Consequently, end portion 114 or 116 will readily swing outwardly about pin 126 or 128 when engaged from one direction but will resist rotation when engaged in the opposite direction. By way of example, assume the mechanism is adjusted to a left turn signaling position similar to that illustrated in Fig. 5, thus causing the inner corner 138 of end portion 116 to intersect the circular path of pin 112. Upon rotation of the steering wheel in a left turn or counter-clockwise direction, pin 112 moves into engagement with the inclined leg 132. Because of the shallow angle defined by leg 132, continued movement of pin 112 readily deflects the straight portion 88 of spring 80 outwardly and permits the end portion 116 to pivot clockwise about pin 128. However, when the direction of rotation of the steering wheel is reversed, pin 112 approaches from the opposite direction and engages the leg 134 of member 116. Because of the high interference angle of leg 134, continued movement of pin 112 induces counterclockwise rotation of member 116, which, in turn, causes leg 88 to swing inwardly until arrested by tab 100 on ring 6. Since end portion 116 is thereafter incapable of counter-clockwise rotation, ring 6 is cammed to neutral position as soon as the rotational pressure of pin 112 exceeds the resilient holdingpressure of detent 40. In the event the operating lever 14 is forcibly retained in the left signal operating position during the cancelling operation, just described, progressively increasing pressure of pin 112 causes temporary local distortion in the triangular configuration 116 and permits the pin to pass. It will, of course, be understood that the triangular configuration 116 resumes its normal form following each overriding cycle and will function in the normal manner to cancel the signal when forcible restraint of the ring 6 ceases.

From the foregoing, it will be seen that a novel, eflicient and highly simplified switch operating mechanism has been provided. It is to be particularly noted that the invention accomplishes, with a single element of simple configuration, all of the functions that have heretofore required a large number of parts. In addition, the number and complexities of assembly operations are greatly reduced, thus permitting low cost high volume production.

While but two embodiments of the invention have been shown and described, it will be apparent that other changes and modifications may be made therein. It is, therefore, not intended to limit the invention to the embodiments shown but only by the scope of the claims which follow.

We claim:

1. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating positions, and stop means formed on said ring adapted to resist deflection of said flexible means in one direction, whereby said cam means is operative to deflect said flexible means when rotated in one direction and to return said ring to neutral position when rotated in the opposite direction.

2. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, a flexible member having its opposite ends secured to said ring, means on said member engageable by said cam means when said operating ring is disposed in either switch operating position, and stop means formed on said ring to resist deflection of said flexible member in one direction whereby said cam means is operative to deflect said flexible member when rotated in one direction and to return said ring to neutral position when rotated in the opposite direction.

3. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, a flexible member having its opposite ends pivotally connected to said ring, means on said member adjacent said pivotal connections engageable by said cam means, said means on said member being swingable in either direction about said pivotal connections against the resistance of said flexible member, rigid stops formed on said ring, said stops being eflective to prevent deflection of said flexible member in one direction whereby said means on said member are rotatively deflectible in one direction .and rotatively arrested in the opposite direction.

4. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, a generally'U- shaped wire spring having integral pawls formed at either end thereof, means pivotally connecting said spring to said ring adjacent said pawls, and stop means on said ring adapted to engage said spring adjacent said pawls to prevent yieldable rotation of said pawls in one direction whereby said pawls are yieldably displaceable responsive to movement of said cam means in one direction and said ring is returned to neutral responsive to movement of said cam in the opposite direction.

5. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position,'rotatable cam means, a generally U- shaped wire spring having inwardly facing looped portions terminating in outwardly extending arms pivotally secured at opposite sides of said ring, each of said loops being swingable about said pivotal connections, and a pair of tabs formed on said ring adjacent said loops and eifective to decrease the flexibility of said spring when said loops are rotated in one direction, whereby rotation of said loops in one direction is resisted by the decreased flexibility of said spring and rotation of the loops in the opposite direction is resisted by the normal flexibility of said spring.

6. In a direction signal switch operating mechanism having a manually settable operating member, means for resetting said operating member comprising a unitary spring having looped portions and a connecting midportion, means pivotally connecting said looped portions to said ring, and additional means on said ring abutting said connecting portions adjacent said looped portions to prevent flexing of said midportion in one direction whereby said midportion offers low resistance to swinging movement of said loops in one direction and high resistance to swinging movement of said loops in the opposite direction, and means rotatively engageable with said loops from either of said directions.

7. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating positions, and stop means formed on said ring adapted to modify the normal flexibility of said flexible means in one direction whereby said cam means is operative to deflect said flexible means when rotated in one direction and to return said ring to neutral position when rotated in the opposite direction.

8. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating position, and stop means formed on said ring eflective to decrease the normal resilience of said flexible means in one direction whereby said cam means is operative to deflect said flexible means when rotated in one direction and to normally return said ring to neutral position when rotated in the opposite direction.

9. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating position, and stop means formed on said ring effective to decrease the normal resilience of said flexible means in one direction, whereby said cam means is operative to deflect said flexible means when rotated in one direction and to normally return said ring to neutral position when rotated in the opposite direction, said flexible means being deflectable in response to rotation of said cam in said opposite direction when said ring is forcibly restrained in either operating position.

10. A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, detent means for resiliently retaining said ring in any of said positions, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating position, and stop means formed on said ring effective to decrease the normal resilience of said flexible means in one direction to less than the resilience of said detent means, whereby said cam means is operative to deflect said flexible means When rotated in one direction and to retain said ring to neutral position when rotated in the opposite direction.

11, A direction signal switch operating mechanism comprising a support, an operating ring pivotally mounted on said support for movement from a central neutral position to switch operating positions at opposite sides of said neutral position, detent means for resiliently retaining said ring in any of said positions, rotatable cam means, flexible means mounted on said operating ring and engageable by said cam means when said operating member is in either switch operating position, and stop means formed on said ring effective to decrease the normal resilience of said flexible means in one direction to less than the resilience of said detentmeans, whereby said cam means is operative to deflect said flexible-means when rotated in one direction and to normally return said ring to neutral position when rotated in the opposite direction, said flexible means being defiectable in response to rotation of said cam in said opposite direction when said ring is forcibly restrained or jammedin either operating position.

12. The structure set forth in claim 3 wherein said means on said member adjacent said pivotal connections comprise generally triangular looped configurations.

13. The structure set forth in claim 3 wherein said means on said member adjacent said pivotal connections comprise generally triangular looped configurations which are normally aligned relative to the path of said cam means to afford a high angle of interference when approached in one direction and a low angleof interference when approached in the opposite direction.

References Cited in the file of this patent UNITED STATES PATENTS 2,690,483 Ellicott et al Sept. 28, 1954 2,691,704 Lincoln et a1. Oct. 12, 1954 2,702,327 Redick Feb. 15, 1955 2,722,577 Barcus Nov. 1, 1955 2,724,750 Brown Nov. 22, 1955 2,725,435 Cislo Nov. 29, 1955 2,731,525 Redick Jan. 17, 1956 

